feat: add windows builds

[elibosley]

Summary by CodeRabbit

• Chores
  • Updated build and release workflows to apply platform-specific extensions to compiled binaries, ensuring Windows binaries are properly named with .exe extensions.

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[coderabbitai]

📝 Walkthrough

Walkthrough

GitHub Actions workflows for parity and release builds are updated to add platform-specific binary extensions. A new matrix field ext is introduced with .exe for Windows and empty string for other platforms, then propagated via environment variable and applied to build output and artifact upload paths.

Changes

Cohort / File(s)	Summary
GitHub Actions Workflow Configuration .github/workflows/parity.yml, .github/workflows/release.yml	Added ext matrix field across OS/arch combinations (.exe for Windows, empty for others). Propagated ext to BIN_EXT environment variable in build steps. Updated binary output paths from dist/apprise-go-${GOOS}-${GOARCH} to dist/apprise-go-${GOOS}-${GOARCH}${BIN_EXT}. Updated artifact upload patterns to include the extension suffix.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Poem

🐰 With whiskers twitching, I hopped with glee,
Windows binaries now .exe they'll be,
Linux and macOS bare their name,
Platform-specific builds, all the same!
Extensions flowing through the matrix so bright,
Our workflows compiled just right! 🎉

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